This research is directed towards developing new methods for synthesis of oxygen-containing natural products. Specific methodology focuses on ketal cleavage reactions to generate properly functionalized oxepane derivatives. Targets include zoapatanol and laurenan. Natural products have played an important role in human medicine and in many places in the world the well-being of communities depends solely on the use of local natural medicines - often from plant sources. One of the significant major improvements in health treatment has been the ability of chemists to synthesize, modify, and prepare analogs of known parmacologially-active constituents of these natural medicines. The synthesis of these materials require special techniques. The proposed program of research is characterized by use of novel methodologies developed in our laboratory to the synthesis of a variety of interesting and biologically-significantly natural products and their analogs. This research subproject has the potential to develop new approaches to the naturally-occurring contraceptive, zoapatonal, as well as gain insight into metal binding to our highly oxygenated ketals and procedures as models for ionophores.